The pair worked together in sessions that yielded three songs which were eventually released by West: "Only One," "All Day" and "FourFiveSeconds," a hit single that featured Rihanna.

“I got a phone call and my manager said, ‘Kanye West would like to work with you,’" McCartney explained to Australian comedian and musician Tim Minchin, who hosted the Facebook live chat (via NME). "And I go, ‘Yeah, we’ll do it.’ I was a little bit nervous at first, because I thought it could go horribly wrong. But I was intrigued to see what he was up to and how he did it.”

McCartney said "it was a very intriguing process. You basically don’t write songs. You basically just talk and noodle a bit and you record it all on your phone. And then he goes away. And that’s basically his record. But it was great doing it because I don’t work like that.”

“So I was waiting three months after we’d finished [recording],” McCartney said. “I didn’t really hear anything but ‘Hey, bro, what’s going on?’ But I’m thinking, should I say, ‘Did we write a song? Will a record come out of this?’ Anyway, this arrives and it’s a Rihanna song. ... I said, ‘This is great! I have to ring up and say, ‘Am I on this?’ And he goes, ‘Oh, yeah. You’re the guitar player.’ I go, ‘I don’t remember.’ And he said, ‘We sped it up.’ So they manipulated this, kind of – although, we’re talking about Sgt. Pepper, we loved manipulating. So I think we would have been into a lot of these tricks nowadays, because we did speed things up a little bit.”

In other McCartney news, a 2009 performance he and former bandmate Ringo Starr gave at the "Change Begins Within" charity concert -- a benefit for the David Lynch Foundation held at Radio City Music Hall -- will be released on DVD for the first time on Sept. 1. Both artists perform several songs on their own, but they joined up onstage for "With a Little Help From My Friends" near the end of the show.